This invention relates to hydrocarbon upgrading processes. In particular, the invention relates to a novel continuous swing reactor-regenerator design.
While previous reactor systems have employed piping configurations to periodically regenerate one of two or more catalyst beds while the remaining catalyst beds are on stream, none have suggested a continuous-swing tubular reactor system providing substantially isothermal reaction conditions and using a reactor effluent slipstream from a first set of parallel reactors to regenerate the catalyst in a second set of parallel reactors. Further, none have suggested a continuous-swing tubular reactor system wherein the tubular reactors are contained in a fired heater and flue gas from said heater is used as a catalyst regeneration gas.
For example, U.S. Pat. No. 3,450,506 to Guerrieri teaches an improved process of steam reforming using tubular reactors having a nickel oxide steam reforming catalyst integrally coated on the inside diameter of the tubular reactors.
U.S. Pat. No. 4,256,783 to Takada discloses a catalytic vapor phase oxidation reactor which comprises a fixed-bed shell and tube heat exchanger in which a tube bundle filled with at least one type of oxidizing catalyst is disposed in a shell. Heat transfer fluid is passed over the outside of the tubes in a multiplicity of zones to control the reaction temperature of the exothermic catalytic vapor phase oxidation reaction occuring inside the tubes.
U.S. Pat. No. 4,430,304 to Spurrier teaches a slab-shaped, high efficiency catalytic reformer comprising a plurality of structures forming a generally rectangular peripheral envelope spaced about one another to form annular regions. The interior annular region contains a catalytic bed and is regeneratively heated on one side by hot combusion gases and on the other by the gaseous products of the reformation.
U.S. Pat. No. 4,461,745 to Ahlstrom discloses a self-regenerating catalytic reactor. The reactor is of the shell and tube type, wherein the head on the first end of the reactor is divided by a partition. A reactant, for example oxygen, is passed into one side of the divided head, passed through the tubes containing catalyst on one side of the reactor which are available to that portion of that head. Upon exiting into the head at the opposite end of the reactor the reactant oxygen is mixed with another reactant, for example a chlorinated hydrocarbon, and fed into tubes on the other end of the reactor, which also contains catalyst, and wherein the oxidation of the chlorinated hydrocarbon occurs. The product gases exit on the side of the divided head opposite the oxygen inlet at the first end of the reactor. A heat exchange medium surrounds the tubes and circulates within the shell to either heat or cool the tubes as necessary. When the catalyst employed in the reaction becomes coated with carbonaceous material, the flow is reversed and the oxygen fed into the side of the reactor containing the deactivated catalyst. This design does not suggest the use of a reactor effluent stream to regenerate the catalyst.